1. lépés: Töltse fel a M4V fájlokat a fenti gombbal vagy húzással.
2. lépés: Kattintson a „Konvertálás” gombra a konvertálás megkezdéséhez.
3. lépés: Töltse le a konvertált fájlt BMP fájlokat
M4V nak nek BMP Konverziós GYIK
How do I extract frames from a M4V video as BMP images?
+
Upload the M4V and the converter exposes a frame-extraction picker: every Nth frame, frames at specific timestamps, or one frame per second. Each chosen frame is encoded as an individual BMP file and the full set is bundled into a ZIP archive for download.
At what resolution does each extracted BMP frame come out?
+
The same resolution as the M4V video — a 1080p M4V produces 1920×1080 BMP frames; a 4K M4V produces 3840×2160 BMP frames. Use the resize utility after extraction if you want smaller thumbnails or social-media-sized crops.
Can I extract every single frame from M4V as BMP?
+
Yes, but be careful with file count — a 30fps 1-minute M4V produces 1,800 BMP frames. We pack them into a ZIP automatically. For longer clips, the "1 per second" option (60 frames) or specific timestamps gives a manageable result.
Will the extracted BMP images preserve the M4V color grading?
+
Yes — colour is decoded with the matrix the source M4V uses (BT.709 for HD, BT.2020 for 4K HDR). HDR sources are tone-mapped to SDR on extraction to BMP because most BMP formats (PNG, JPG) cannot store HDR pixel ranges natively.
What is the file size of one extracted BMP frame?
+
Depends on resolution and BMP codec. A 1080p PNG frame is typically 2 to 5 MB; a 1080p JPG at quality-85 is 200 to 500 KB; a 4K PNG is 6 to 15 MB. At the extreme, every-frame PNG extraction of a 10-minute 1080p M4V produces ~50 GB total.
Does the extracted BMP retain EXIF camera metadata?
+
The M4V container does not store per-frame EXIF the way a still camera does, so the BMP files come out with empty EXIF. We embed a `creation_time` field pointing at the source frame timestamp so you can re-sort the bundle by capture order.
How long does frame extraction from M4V to BMP take?
+
Frame extraction is fast — typically 20 to 30% of source duration on the standard pipeline. A 5-minute M4V → BMP bundle finishes in about a minute regardless of frame count, because the bottleneck is the BMP encoder, not the M4V demuxer.
Can I extract frames at specific timestamps in the M4V?
+
Yes — the advanced option accepts a comma-separated list of timestamps (e.g. `00:01:23,00:05:00,00:10:42`) and produces one BMP file per timestamp. Useful for chapter thumbnails, scene reference shots, or thumbnailing long lectures.
Is my M4V video private during frame extraction?
+
Yes — same privacy model as every conversion. Source video and extracted BMP frames are processed in isolated workers and deleted within minutes; no human review, no training corpus, no third-party access.
Why are my extracted BMP frames blurry?
+
Almost always motion blur baked into the M4V source — the camera or subject was moving when the frame was captured. Pick timestamps from static scenes, or extract adjacent frames and choose the sharpest. The pipeline does not synthesize detail that was not there.
Can I extract one BMP per scene change rather than per timestamp?
+
Not in the basic flow — use the "1 per second" option as an approximation, then visually pick scene-change frames. A dedicated scene-detection extractor is on the roadmap; ping us if it would unblock a specific workflow.
Can I use the extracted BMP frames commercially?
+
Yes, subject to whatever licence governs the source M4V content. The format change adds no claim — we add no watermark and assert no licence over the BMP output. Copyright tracks the source, not the converter.